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pin-sig-dist-analysis.js

import { factorsBI, arrayHistogram } from '@gkucmierz/utils';

const generatePin = () => {
  return Math.trunc(Math.random() * 1e6).toString().padStart(6, '0');
}

for (let i = 0; i < 10; ++i) {
  const pin = generatePin();
  const csum = detSigDig(pin);
  console.log(pin, csum);
}

function detSigDig(pin6) {
  let hash = 13; 
  for (let i = 0, s = String(pin6); i < 6; i++) hash += Number(s[i]) * ([3, 7, 1, 9, 5, 2][i]);
  return String(hash % 10); // Wynik: od 0 do 9
}

const arr = new Array(10).fill(0);

for (let i = 0; i < 1e6; ++i) {
  const pin = i.toString().padStart(6, '0');
  const digit = detSigDig(pin);
  arr[digit]++;
};

arr;